Head shaft mounting and assembly for sludge removing apparatus



Aprifl 193% s. SHAFER, JR Lggfigm HEAD SHAFT MOUNTING AND ASSEMBLY FOR SLUDGE REMOVING APPARATUS Filed Dec. 2, 1931 2 Sheets-Sheet l Sam ((04 Sh/cgfal; Jr;

HEAD SHAFT MOUNTING AND ASSEMBLY FOR SLUDG-E REMOVING APPARATUS FiledDec. 2, 1931 2 Sheets-Sheet 2 Patented Apr. 24, 1934 HEAD SHAFT MOUNTING AND ASSEMBLY FOR SLUDGE REMOVING APPARATUS Samuel Shafer, Jr., Milwaukee, Wis, assignor to Chain Belt Company, Milwaukee, Win, a corporation of Wisconsin Application December 2, 1931, Serial No. 578,600 3 Claims. (01. 210-55) This invention relates to head shaft mountin s and assemblies for sludge removing apparatus, such as is commonly employed in settling tanks of liquid separation and purification systems, and

has for one of its objects to provide a device of this character which will be simple in construction, comparatively inexpensive to manufacture and more efllcient inuse than those which have been heretofore proposed.

In the removal of settled solids, commonly known as sludge, from the settling basins or tanks of liquid separation and purification systems, such for example as a sewage disposal system, it is common to provide a sludge removing conveyor comprising a pluralityof spaced endless chains trained about sprockets carried by transverse shafts mounted within the settling tank or basin. the said chains being provided with transverse flights or scrapers which during their lower run move over the bottom surface of the basin and scrape the settled sludge therefrom to a well or sump at one end of the tank. Such conveyors are moved at a relatively low rate of speed from any suitable source of power, which power is applied through one of the transverse shafts commonly known as the head shaft.

The said shafts are ordinarily joumalled in bearings which may be attached to the side walls of the basin or supported in any other suitable manner and the sprocket wheels which support and guide the conveyor chains are usually spaced some distance from the ends of the shafts. On

' the tank to accommodate the driving sprocket struction which is cantilevered from the side wall wheel-about which is trained the power supplying chain or belt from the source of power. This driving sprocket has heretofore been mounted at the extreme end of the head shaft and in order to properly support and journal this end of the said shaft, it has been necessary to employ a special journal bearing of extremely heavy conof the tank and receives the head shaft at a point intermediate the drive sprocket and one of the conveyor chain guiding sprockets.

Such a mounting for the head sprocket, as above pointed out, involves the use of an e2":- tremely heavy bearing casting or structure since of the various shafts, while at the same time the weight of the conveyor chains and flights is considerable, which bearing must be difierentfrom all the rest employed in the installation and specially made at considerable additional expense. In the prior constructions it has not been possible to utilize the same type of hearing which is employed at the other end of the head shaft or at the ends of the idler shafts since the use'of such bearings would necessitate the placing of 5 the drive sprocket inside of the bearing where it would interfere with the ends of the flights or scrapers during their travel.

It is the primary object of the present invention to overcome this previous difficulty and to g provide a head shaft mounting and assembly for apparatus of this type in which the drive sprocket end of the head shaft may be journalled in substantially the same manner as are the other ends the drive sprocket may still be positioned so as not to interfere with the conveyor flights during their travel. The construction furthermore is such as to provide for ready access to the hearing, which is preferably of the split type having a removable cap, whereby the said cap may be readily assembled" and disassembled in case of necessity, without interfering with other portions of the assembly.

with the above and other objects in view which will appear as the description proceeds, the invention consists in the novel details of construction and combinations of parts more fully-hereinafter described and particularly pointed out in the appended claims.

Referring to the accompanying drawings forming a part of this specification in which like reference characters designate like parts in all the views:--

Figure 1 is a vertical longitudinal sectional view through the influent end of a settling tank or basin such as is widely employed in-sewage disposal plants, illustrating the use of the present head shaft assembly therein;

Figure 2 is a fragmentary horizontal sectional plan view,-on an enlarged scale, taken approximately on the plane indicated by the line 2-2 of Figure 1; I

Figure 3 is an elevational view looking in the same direction as Figure 1, of the bearing in place upon the side wall of the settling tank; a

Figure 4 is a transverse vertical sectional view partly in elevation, on an enlarged scale, taken approximately on the plane indicated by the line 44 of Figure 1; and

Figure 5 is .a vertical sectional view taken apidler shafts 17 and the head shaft 18.

proximately on the plane indicated by the line 55 of Figure 4.

Referring more particularly to the said drawings, indicates generally a settling tank or basin, which is or may be constructed of concrete as indicated, and which is provided with an influent channel 11 adapted to feed raw sewage or other solid-carrying liquid which is to be purified into the tank 10 through port 12 which may be controlled by a suitable gate, not shown. The basin 10 is provided at this end with the sludge sump or well 13 intowhich the settled solids or sludge may be moved through the well known action of the conveyor flights or scrapers 14 carried by the endless chains or belts 15, which are trained about the sprockets 16 carried by the The said head shaft 18 is supplied with power through a sprocket 19, which in the present instance is of special construction, about which sprocket is trained a drive chain 20 which receives power from a sprocket 21 carried by the shaft 22 of a motor driven speed reducing gear, all as is well known in the art.

As is best shown in Figures 2, 3, 4 and 5, the extreme end of the head shaft 18 which carries the driving sprocket 19 is journalled in a hearing structure 25, which is or may be substantially the same as those employed to journal the other end of the said shaft as well as the ends of the various idler shafts, thus making all these bearings uniform. The bearing structure as here shown comprises a bracket 26, the vertical back plate of which is positioned against the side wall 27 of the tank 10 and is secured thereto as by bolts 28, embedded in the concrete of the wall. The said bracket is further provided with a horizontal extension 29 which constitutes the lower half of the journal for the shaft and to which extension may be detachably secured as by bolts 30 a removable cap 31, which constitutes the upper half of the journal. The said cap is preferably provided with an upwardly facing arcuate surface 32 which is concentric with the axis of the shaft 18, as will be clear from Figures 3 and 5.

As will be clear from Figures 2 and 4 the ends of the flights or scrapers 14, which as above explained extend substantially to the side walls of the basin, project beyond the inward end of the bearing structure 25 and should a drive sprocket of ordinary construction be mounted inwardly of the said bearing it would not be cleared by the ends of these flights. To provide for this contingency a drive sprocket is mounted upon the shaft 18, having a hub portion 35 and a rim portion 36 which are connected by web portion 37, and as will be clear from Figures 2, 4 and 5, the

said web is inclined or dished intermediate the hub and the rim so as to surround the horizontal portions of the bearing structure 25 and thereby offset the rim of the sprocket toward the side wall, as clearly shown in Figures 2 and 4. This offsetting brings the said rim portion which receives the drive chain 20, into alignment with the opening 38 formed in the top wall 39 of the basin for accommodation of the chain 20, and a portion of said sprocket may project into the recess 40, which is usually provided in the side wall 2'7. The said sprocket may be solid but is preferably of the transversely split type as clearly shown in Figures 4 and 5 with the two sections'thereof being held in assembled relation by suitable bolts 41' and 42.

In order to afford ready access to the bearing structure 25, which is thus more or less housed by the sprocket 19, so as to permit of the removal of the bearing cap 31 in case of necessity after the apparatus is installed, the web portion 37 of the sprocket is cut away at suitable points to provide the relatively large apertures 43 and the small apertures 44. The remaining portions 45 of the web 37 thus in effect constitute spokes, and the relatively large apertures 43 when the sprocket is turned to the position shown in Figures 2 and 5 aiford ready access to the bolts 30 which normally hold the cap 31 in position, as well as to the cap itself, whereby the latter may be readily removed and replaced without dismounting the sprocket, as will be readily understood.

In many forms of clarification and liquid purification work it is highly desirable or necessary to prevent accumulations of settled solids upon various stationary portions of the apparatus, such for example as the upper surfaces of the bearing structures such as 25. In the present instance such accumulations upon the upper surface 32 of the bearing cap 31 are constantly removed by a bar or scraper carried by the web portion 3'7 of the sprocket 19 as shown in Figures 2, 4 and 5, which scraper is so positioned relative to the bearing as to sweep across the arcuate vary the details of construction as well as the precise arrangement of parts without departing from the spirit of the invention, and therefore it is not wished to be limited to the above disclosure except as may be required by the claims.

What I claim is:

1. In settling tanks and the like, a shafthaving sludge-conveyor supporting means spaced from an end thereof; a bearing structure mounted within the tank adjacent a wall thereof, for re ceiving and journalling the extreme end portion of said shaft; and a power transmission'wheel within the tank having a hub portion secured to said shaft intermediate said bearing and conveyor supporting means and a rim portion ofiset relative to said hub to clear the flights of the sludge conveyor.

2. In settling tanks and the like, a shaft carrying sludge-conveyor supporting means spaced from an end thereof; a split bearing structure within said tank having means for normally securing its parts in assembled relation to receive and journal the extreme end portion of said shaft; and a power transmission wheel within the tank having a hub secured to said shaft intermediate said bearing and conveyor-supporting means and a rim portion offset relative to said hub to clear the flights of the sludge conveyor, said wheel being provided intermediate its hub and rim with apertures through which access may be readily had to the removable portion of said split bearing and the securing means therefor.

3. In settling tanks and the like, a shaft carrying a sludge conveyor supporting wheel spaced from an end thereof; a bearing structure within said tank, including a bracket secured to a wall li b of the tank and a cap having a curved upper surface removably secured to said bracket, for receiving and journalling the extreme end portion of said shaft; 2. power transmission wheel within the tank having a hub secured to said shaft intermediate said bearing and conveyor-supporting wheel, a rim, and a web connecting said hub and rim, said web being cut away to provide apertures through which access may be readily had SAMUEL SHAFER, JR. 

